It is often desirable to stretch and exercise a shoulder to increase the shoulder's strength, flexibility, and range of motion. For example, physical therapy programs, that include strengthening, stretching, and/or range of motion exercises, are often prescribed to assist a patient's recovery from shoulder injury. Assistive, passive exercises such as shoulder rotation and stretching exercises are generally recommended to rehabilitate the shoulder rather than active exercises. In a passive exercise, the shoulder is stretched and rotated in a manner that does not involve the tensing or exertion of the target shoulder muscles. In an active exercise, the target shoulder muscles are tensed or exerted during the exercise.
One therapeutic technique often employed is to stretch the shoulder through internal and external rotation. For example, a physical therapist may arrange the patient's arm in a desired position and rotate the arm through a desired rotation plane in order to stretch the shoulder. By supporting the user's arm and isolating the shoulder as a desired pivot point, a passive stretching is obtained which allows movement of the shoulder without tightening the target shoulder muscles. The therapist can move the arm into various positions to allow for both internal and external rotation of the shoulder in a variety of different planes. While this method works well, it requires the assistance of a physical therapist or other assistant to provide the necessary support and movement force.
Rehabilitation is most effective when a patient performs the exercises on a frequent basis, such as several times daily. Patient participation in an exercise program is usually increased if the patient can perform the exercises within the framework of his or her daily activities without the necessity of traveling to a special facility for ongoing supervision or specialized equipment. Exercise programs which can be performed by the patient in the home or the workplace without the assistance of a physician or physical therapist are desirable as it increases the availability and frequency of the exercise sessions.
But it is difficult for a patient to perform therapeutic programs without assistance from a physical therapist or other aide. Even with the aid of a physical therapist or other assistant, it has been proven difficult to apply a steady, safe, and consistent force to the shoulder for both internal rotation and external rotation. The extent to which the shoulder-related muscles are stretched or exercised can vary considerably between exercise sessions and even between different repetitions of the same session. When a person other than the patient is providing the force for the stretch, he must rely on the patient to tell him what the patient is feeling during the stretch, thereby making if difficult to determine the optimum stretch and obtain consistent exercises. Furthermore, it is difficult to document the amount of rotation or force exerted by the shoulder, thereby making it difficult to monitor a patient's performance and progress.
A number of shoulder rehabilitation devices have been developed. Most prior art devices, however, suffer from the fact that they are narrow in their purpose, only providing for movement in a limited number of planes and lacking the versatility to provide the full range of shoulder exercises that a patient may require. In addition, most devices do not provide for passive stretching in both internal and external rotation as well as both exercising and stretching. Furthermore, some equipment is large and bulky, making it difficult for a user to transport the device to the home and office, and thereby limiting the availability of the device and decreasing the frequency of sessions.
U.S. Pat. No. 5,352,174 to Mason discloses an active shoulder exercise system in which a patient moves his arm against the elastic resistance of an elastomeric tube while the device is anchored to the foot of the patient or a door jamb. While fit for its intended purpose, that device does not provide for passive movement, as it requires a user to grasp the device with the arm of the shoulder being rehabilitated, thereby tensing the shoulder muscles.
U.S. Pat. No. 5,520,615 to Fontana et al. discloses a self-assisted shoulder stretching and rotation machine in which one end of a rope is attached to each side of a forearm support to form a continuous loop. The patient lies in a supine position securing a forearm to the forearm support and pulling one end of the rope to move the forearm support in a first direction. While fit for its intended purpose, that device is not readily portable, does not provide for movement in a multitude of planes, is limited to a 180 degree range of motion (90 degree external and 90 degree internal), and requires that the patient be in a supine position.
Thus, there is a need for an apparatus and method that allows a user to perform passive stretching of the shoulder in both internal and external rotation and a broad range of shoulder stretches and exercises without the necessity of constant medical supervision or assistance from others. A shoulder apparatus is also needed which is portable and allows a user to perform exercises and stretches in a variety of different locations. A shoulder apparatus and method is also needed which provides for both stretching and exercise in an infinite number of planes. There is also a need for a shoulder stretching and exercise device that can be used by a user in a sitting, standing, supine or other position. There is also a need for an apparatus that allows a user to measure the stretching and exercise of the shoulder. There is also a need for an apparatus and method that fulfills the above-recited needs, yet which is relatively inexpensive to produce and maintain.